unit Class_Test;

interface
uses
  Classes,SysUtils,Dialogs, XMLDoc, XMLIntf;
type
  IXMLOperate=interface
  ['{CE799A6C-CD18-49CD-B5A4-BF052C4C159D}']
    procedure SayHelloWorld;
  end;

  TTest=class(TInterfacedObject,IXMLOperate)
  public
    procedure SayHelloWorld; virtual;
  end;

  THelloWorld=class(TTest)
  public
    procedure SayHelloWorld;override;
  end;

implementation

{ THelloWorld }

procedure THelloWorld.SayHelloWorld;
begin
  inherited;
  showmessage('HelloWorld');
end;

{ TTest }

procedure TTest.SayHelloWorld;
begin
  ShowMessage('helloworld first');
end;

end.
